Centering device for electric switches.



A. C. SMITH.

CENTERING DEVICE FOR ELECTRIC SWITCHES.

APPLICATION FILED JAN.5, 1911.

L143Q8 4 Patented May 25, 1915.

THE NORRIS PETERS CO-, PHOTO-LITHQ, WASHINGTON, D. C-

'UNTTE STATS TATENT FIFTQE.

ALLEN C. SMITH, OF YONKERS, NEW YORK, ASSIGNOR TO OTIS ELEVATQR COMPANY, OF JERSEY CITY, NEW JERSEY, A CORPORATION OF NEW JERSEY.

CENTERING DEVICE FOR ELECTRIC SWITCHES.

Specification of Letters Patent.

Patented May 25, 1915.

Application filed January 5, 1911. Serial No. 600,878.

To all whom it may concern Be it known that I, ALLEN C. SMITH, a citizen of the United States, residing at Yonkers, in the county of I/Vestchester and State of New York, have invented a new and useful Improvement in Centering Devices strong in construction, and effective and efiicient in operation.

In certain classes of electrical switches it is desirable that as soon as the hand of the operator leaves the hand lever it should be returned to a central or ineffective position. This switch centering device eliminates all danger of inattention or carelessness of the operator, and provides for the automatic re turn of the switch to central position.

The invention may have a broad and general application and is especially adapted and designed for an elevator car switch.

Referring now to the accompanying drawing, a preferred embodiment of the invention is shown, which comprises a contactswitch in connection with the centering de: vice. The hand lever 1 is secured to the member 2 which carries the gear segment 4 and is revolubly mounted by means of the pivot 3; so that the hand lever 1 rotates about the pivot 3 as a center. The guard 6 is provided with stops 7 which limit the movement of the hand lever 1 in either direction. Meshing with the gear segment 4 is the gear wheel 5 which is rotatable about the pivot 8. The contact segment 9 is secured to and rotates with this gear wheel 5, and as the contact segment is moved about the pivot 8, it makes connection with the contacts 10 or 11. The lower portion 2 of the pivoted member 2 is connected with the centering device. The centering device includes; a rod 14: mounted at its ends in the projections 16 of the switch casing 12 and secured by means of the cotter pin 15; a compressible coil spring 17 mounted upon the rod; a sleeve-shaped abutting member 18 at each end of the spring, recessed to receive the spring and threaded on the outside. The threaded member or nut 19 is movable on the threaded portion of the member 18 and the pressure of the spring 17 is varied by the movement thereof. Threaded nuts 23 are movable on the threaded portions of the members 18 and are provided with projecting pins 21; the slotted links 20 are loosely fastened to the pin 22 in the pivoted member 2, and the slotted portions are adapted to slide along the pins 21 carried by the nuts 23. It is to be understood that there are two slotted links 20, one extending each way from the pivoted member 2, and making connections between the pin 22 and the two pins 21. When the pivoted member 2 is moved in either direction by the hand lever 1, the spring 17 is compressed from the opposite end; for instance, if the lower portion 2 is moved to the left, the left slotted link 20 (not shown) will slide along the corresponding pin 21, while the right slotted link 20 will engage the pin 21 as soon as the movement is commenced, and will cause the sleeve member 18 and the nut 19 to move in accordance therewith, thereby compressing the spring 17 As soon as the hand lever 1 is released, the spring returns the displaced members to their normal positions. By adjusting the position of the nut 23 along the threaded portion the compression of the spring 17 may be delayed until the hand lever is moved a short distance, and by moving the nuts 19 farther out on the threaded portion the compression of the spring is 1ncreased. The projections 16 act as buffers for the return impact of the sleeve members 18 and the nuts 19 caused by the spring 17.

It is evident that the centering device is readily adjustable, and the arrangement of parts is such that repairs may be easily and quickly made.

While I have thus specifically described the preferred combination and arrangement of my invention, it is to be understood that I wish not to be limited thereto, for those skilled in the arts to which this appertains may make various changes without departing from the spirit and scope of the mvention.

What I claim and desire to secure by Letters Patent of the United States is 2- 1. In a centering device, the combination of a member movable to either side of a central position, a compressible coil spring, sleeve-shaped abutting members at the ends thereof, nuts threaded on said abutting members and forming adjustable extensions to vary the position of the abutting members and thereby Vary the compressible strength of the'spring, stops for said nuts, and slotted links connecting each abutting member with the first-named member.

2. In a centering device, the combination of a member movable to either side of acentral position, a compressible coil spring to return the member to central position, an abutting member at each end of the spring, slotted links connected to said first-named member, and connecting devices between the abutting members and said links, said connecting devices being adjustable with respect to said abutting members to vary the efi'ective length of said links.

8. In a centering device, the combination of a member movable to either side of a central position, a compressible coil spring, abutting members at the ends thereof formed with a sleeve shaped projection threaded on the outside, a nut movable on said threaded portion, and slotted links connecting the said nuts and the first named member to effect the automatic return of the latter to central posit-ion when moved therefrom.

4. In a centering device, the combination of a member movable to either side of a central position, a fixed rod, a compressible coil spring mounted upon the rod, a sleeveshaped abutting member at each end of the spring provided with outside threads, nuts movable on said threads, and slotted links connecting the nuts and the first named movable member.

5. In a centering device, the combination of a hand lever movable to either side of a central position, a rod, a coil spring about the rod, threaded sleeve-shaped abutting members at each end of the spring and movable on the said rod, adjustable nuts mounted on the said threaded members, and slotted links connecting the handle to one of the nuts at each end of the spring.

6. In a centering device, the combination of a hand lever pivotally mounted, a rod substantially at right angles to the said lever in its central position, a compressible coil spring about the rod, threaded abutting members upon the rod at each end of the spring, movable nuts on the abutting mem bers, and links to connect one arm of the lever and at opposite ends of the spring to effect the return of the hand lever tocentral" position when the spring has been compressed in either direction. I j

7 In a centering device, the combination of a member movable to either side of the central position, a compressible coil spring, an abutting member at each end thereof, stops for said abutting members, said abutting members beingprovided with adjusting means to vary the positions of theends of the springs when the abutting members are against said stops, and means connecting the first named members to each of the said abutting members.

8. In a centering device, the combination of a member movable to either side of the central position, a compressible coil spring, a movable abutting member at each end of the coil spring, adjustable nuts forming extensions of said abutting members, stops to limit their movement and slotted links 0011- necting the first named member to each of the said abutting members.

9. In a centering device, the combination of a member movable in either direction from a central position, a rod, a coilspring mounted thereon, members slidably mounted on the rod, connecting means between said slidable members and said first named member, and

adjustable extensions on the slidable mem-" bers forming adjustable stops therefor,

10. In a centering device, the combination of a member movable in opposite directions from a central position, a coil spring, screw threaded members forming abutments for the spring, nuts adjustable on said threaded members, and links connecting said threaded members and the said first named member. 1

11. In a centering device, the combination of a member movable froma central position in either direction, a coil spring, screw threaded members forming abutments for the spring, nuts adjustable on said threaded members, links connecting said threaded members and the said first named member, stops for the screw threaded members, and nuts on the threaded members adjustable to vary the stop positions of the latter.

In testimony whereof, I have signed my name to this specification in the presence of Copies of this :patentmay be obtained. for five cents each, by addressing the Commissioner ofl Patents,

' Washington, D. G." r 

